JPH0716629B2 - centrifuge - Google Patents

Description

Description: TECHNICAL FIELD The present invention includes a separation chamber, an inflow portion into the separation chamber, and three outflow portions from the separation chamber, the first outflow portion of which is the center of the separation chamber. Located in the vicinity, the second outflow portion is located at the periphery of the separation chamber,
Further, the present invention relates to a centrifuge having a rotor in which the third outflow portion is located at a radial center between the first outflow portion and the second outflow portion.

The centrifuge comprises a device for intermittently opening the second outlet during operation of the rotor, a stationary outlet for flowing liquid through the third outlet and further through a fixed conduit. Throttling means for limiting the flow rate through the fixed conduit, and detecting means for detecting when the interface layer between the separated light and heavy liquid components in the separation chamber has been moved radially inward to a predetermined level. A detection means and a control means arranged to cooperate with the opening means for transmitting a signal to the opening means for opening the second outflow portion when the interface layer reaches a predetermined level. Including further.

[Conventional technology]

A centrifuge of this type, which can be used, for example, in connection with the removal of mineral oils from water and solids, is described in Swedish patent specification 348,121 (corresponding to US Pat. No. 3,752,389). This known centrifuge includes a circulation conduit, which is in static communication with the outflow device and which allows the liquid flowing out of the separation chamber of the rotor through the third outflow portion thereof to enter the centrifuge. It is arranged to return to the department. A throttling device for limiting the flow rate of the liquid flowing through the conduit is arranged in the circulation conduit. A branch conduit starts at a location in the circulation conduit between the stationary outflow device and the throttle device, and a closing valve is inserted in this branch conduit.
This shut-off valve is connected to a special detection device and is arranged to open in response to a signal from the detection device. This detection device can also send a signal to the abovementioned opening device of the centrifuge for intermittently opening the peripheral outlet of the separation chamber, the so-called sludge outlet.

When this known type of centrifuge is activated, the separated light weight liquid components, such as oil, are first discharged from the separation chamber through both the central first outlet and the third outlet. It The liquid discharged from the separation chamber through the third outlet is recirculated to the inlet of the centrifuge, this action being separated during a certain predetermined time or in a certain amount, for example water. Continue until heavy liquid components are collected in the separation chamber. When the above predetermined time has passed,
The sludge outlet is opened and all or part of the collected water is discharged from the separation chamber together with the separated sludge.
When said amount of water is collected in the separation chamber prior to the predetermined time, the shut-off valve in said branch conduit is opened so that the separated water flowing out through the third outlet is ,
Instead of returning to the inlet of the centrifuge, it is discharged from the recirculation conduit through the branch conduit.

[Problems to be Solved by the Invention]

A disadvantage of the known device described above is that the stationary effluent device causes an undesired increase in temperature of the separated light weight liquid components discharged from the separation chamber through the third outlet. This rise in temperature is due to the fact that the outflow device, commonly referred to as the separation disc, is in the separated light weight liquid component rotating at the same speed as the rotor in the chamber of the diversion chamber located in the central part of the rotor. It lies in the fact that it is relatively deeply immersed. This immersion depth must be large enough to force the above outflow device radially outwards to the separated heavy liquid components instead of the light liquid components in the separation chamber in the subsequent stages of separation. I have to. Therefore, in the latter stage of the above, the free liquid level in the diversion chamber will occupy a position farther from the center of the rotor than when the separated light weight liquid component is contained in the diversion chamber.

During operation of the rotor, the static outflow device having a fairly large surface in contact with the rotating lightweight liquid component means that a large amount of energy is wasted.

Another disadvantage of the known device mentioned above is that special changes must be made to the device used as soon as the density of the separated liquid component changes. For this reason, if a different density, such as oil, is to be removed, a new so-called gravity disc (in the annular member forming the overflow outlet 24 in the centrifuge according to said Swedish patent specification 348,121) is used. Equivalent) must be inserted. Therefore, this known device is unsuitable if there is a change in the density of the separated liquid components during operation of the centrifuge.

The object of the invention is to avoid the abovementioned disadvantages of centrifuges of the type mentioned at the outset by means of a simple and inexpensive device.

[Means for Solving the Problems]

It is an object of the invention, according to the invention, to provide a structure in which the throttling device has a smaller flow capacity than the stationary conduit described above and is formed in the rotor between the third outlet and the stationary outlet. It is achieved by

This allows the stationary outflow device to extend radially outward to the desired level in the rotor, which always corresponds to the level of the free liquid level in the separation chamber of the rotor, without the separated lightweight liquid components flowing around it. Can be made.

In a preferred embodiment of the invention, the throttling means is in communication with a chamber into which the stationary outflow device extends, and a third outflow and in which one free liquid level is present during operation of the rotor. Such a distance is provided in the partition member formed in the rotor between the space extending radially inward in the rotor.

〔Example〕

BEST MODE FOR CARRYING OUT THE INVENTION With reference to the drawings, the present invention will be described in detail below with respect to an embodiment of the present invention.

The centrifuge shown in FIG. 1 has two rotor parts 1 and 2
Of rotors, which are axially united by a stationary ring 3. In the rotor,
A separation chamber 4 is formed in which a set of conical separation disks 5 is arranged.

The separating disc 5 is mounted on a so-called distribution member 6, which is mounted on a bottom plate 7 supported by the lower rotor part 2. A central cavity 8 in the distribution member 6 communicates with the separation chamber 4 through an inlet 9 between the lower part of the distribution member and the bottom plate 7.

In the central cavity 8 a stationary inflow pipe 10 extends for the mixture to be centrifugally processed in the rotor. Outside the rotor, the inflow pipe 10 is connected to an inflow conduit 11 equipped with a shutoff valve 11a.

The rotor has a plurality of peripheral second outflows 12 in the form of ports extending through the lower rotor part 2. These second outflow portions 2 are normally closed with respect to the separation chamber 4, but are intermittently communicated with the separation chamber 4 by the axial movement of the annular sliding member 13 during the operation of the rotor. The sliding member 13 abuts along its peripheral edge an annular gasket 14 engaged in a groove formed in the upper rotor part 1.

A closed chamber 15 for the working liquid is formed between the sliding member 13 and the lower rotor part 2. The closed chamber 15 has a central inlet 16 and a peripheral outlet 17 for the working liquid. The peripheral outflow 17 is significantly narrowed and therefore has a considerably smaller flow capacity than the central inflow 16. The central inlet 16 communicates with the central chamber 18 and a liquid level is maintained in the central chamber 18 by a stationary inlet member 19 during operation of the rotor. The inflow member 19 is a conduit 20.
A closing valve 21 is arranged in this conduit.

A conical partition member 22 is placed on the separation disk 5. This partition member has an annular flange 23 at its center.
And 24 form a central outflow 25 which opens radially inward. The radially inner edge of the lower annular flange 23 is
The first outflow portion 23a, which is an overflow outflow portion for the liquid in the separation chamber 4, is configured during the operation of the rotor.

A stationary flow diverter member 26 extends into the central outflow chamber 25 to a level radially outward of the level of the first outflow portion 23a.
The stationary flow-dividing member 26 is supported by the inflow pipe 10 and forms an annular passage 27 around it, which connects the central outflow chamber 25 and the outflow conduit 28.

The rotor portion 1 has a partition member 29, which is an annular flange, and an end wall 29a on the axially upper side, that is, above the conical partition member 22. Between the annular flange 29 and the end wall 29a, the rotor part 1 is a separate outflow chamber which opens radially inward.
Forming 30. A stationary flow-dividing member 31 extends into the outflow chamber 30, the flow-dividing member 31 being supported by the inflow pipe 10 via a stationary flow-dividing member 26 and forming an annular passage 32 connecting the outflow chamber 30 to a fixed conduit 33. .

The outflow chamber 30 communicates with the flow dividing chamber 4 as follows.

A plurality of radially extending passages 34 are formed between the rotor portion 1 and the partition member 22. The radially outward opening of this passage 34 forms a third outflow 35 from the separation chamber 4. The passage 34 opens radially inward into the channel chamber 36, which is radially inward and is arranged between the annular flange 24 and the annular flange 29. Annular flange 29
The flow path chamber 36 communicates with the outflow chamber 30 through one or several axial throttle holes 37 (FIG. 2) passing through. The throttling hole 37 as a throttling means has a flow capacity that is considerably smaller than the flow capacity with which the flow dividing member 31 can flow out the liquid from the outflow chamber 30.

A flow rate detection device 38 is connected to the fixed conduit 33, which flow rate detection device 38 is further connected to a control unit 39. The previously described shut-off valve 21 in the conduit 20 for supplying working liquid is also connected to this control unit 39. The broken lines 40 and 41 in FIG.
Control unit 39, flow rate detector 38, and control unit 39
Electrical connection lines between the closing valve 21 and the closing valve 21 are shown respectively.

The fixed conduit 33 opens into a container 42, which constitutes the collection container for the mixture to be processed in the centrifuge. Therefore, as can be seen from FIG. 1, the above-mentioned inflow conduit 11
Is connected to the container 42. The arrow 43 indicates the inflow state of the mixture into the container 42.

The illustrated centrifuge operates as follows in separating water and relatively heavy solids.

At start-up of the centrifuge, the closing valve 21 is opened and the working liquid is supplied to the closing chamber 15. A device (not shown) is used to adjust the liquid level in the central chamber 18 to a desired level. The working liquid passes through its outlet 17 and closes the chamber.
An amount corresponding to the amount of the working liquid leaving 15 is supplied from the central inflow portion 16. In this way, the sliding member 13,
The separation chamber 4 is occupied at its week edge in the position shown closed.

After this, the mixture to be centrifugally processed is fed into the central cavity 8 via the inlet conduit 11 and the inlet pipe 10. From this central cavity, the mixture further flows into the separation chamber 4 through the inflow section 9.

The separated oil overflows the first outflow portion 23a and leaves the separation chamber 4, and is discharged from the central outflow chamber 25 to the outflow conduit 28 by the stationary flow dividing member 26.

The separated water and the separated solid matter are collected in the radially outermost portion of the separation chamber 4. While the amount of water and solids separated in the separation chamber 4 is extremely small, the separated oil also flows out of the separation chamber through the third outlet 35 and the passage 34. The separated oil further flows into the flow passage chamber 36, and also flows out from the flow passage chamber 36 through a throttle hole 37 serving as a throttle means.
Flow into. The flow-dividing member 31 transfers the oil to the annular passage 32 and the fixed conduit.
It is sent via 33 into the container 42, and this oil is supplied to the separation chamber 42 with the mixture newly supplied from the container 42.

As described above, the throttle hole 37 has a flow capacity considerably smaller than that of the flow dividing member 31 and the conduit 33. This means that the free liquid level in the outflow chamber 30 occupies a considerable radial distance from the rotor axis, so that the outer part of the flow diverting member 31 is covered with liquid to a very small extent ( (As clearly shown in FIG. 2). Therefore, the heat generated as a result of the relative movement between the oil in the outflow chamber 30 and the flow dividing member 31 can be kept to a minimum.

When oil flows through the fixed conduit 33, the flow rate of this oil is detected by the flow rate detecting device 38. The detected flow rate value is compared with a predetermined value in the control unit 39. The control unit 39 is inactive while the flow rate in the fixed conduit 33 is greater than a predetermined value.

As much water and solids are separated and collected in the separation chamber 4 as water reaches the third outlet 35, the supply of liquid to the passage 34 and thus the flow passage chamber 36 is reduced. Separation chamber 4
The free liquid level in the flow path chamber 36, which is located at substantially the same level as the overflow liquid level of the first outflow portion 23a (FIG. 2)
Subsides with the above-mentioned reduced supply, i.e. this free surface moves radially outwards. As a result, the aperture 37
To the outflow chamber 30 will be reduced, and as a result, the flow of liquid through the fixed conduit 33 will also be reduced.

When the flow rate in the fixed conduit 33 drops below said predetermined value, the control unit 39 closes the closure valve 21 in the conduit 20 for the working liquid for a very short time of a predetermined length. . Therefore, the pressure in the closed chamber 15 is reduced and the sliding member 13 is pushed down by the pressure in the separation chamber 4, so that the second outflow portion 12 is opened. When the closing valve 21 is opened again, the newly supplied working liquid causes the sliding member 13 to return to its closed position together with the working liquid still remaining in the closing chamber 15. Therefore, in this case, only a part of the content in the separation chamber 4 flows out through the second outflow portion 12. Then, only the separated solid matter and water are discharged.

When the flow rate in the fixed conduit 33 is increased again to a value greater than the predetermined value, the above-mentioned working process is repeated.

In the centrifuge described above, all water separated from the oil is thus removed from the separation chamber through the peripheral outflow, which is the second outflow used to remove the separated solids. It Moreover, any liquid discharged from the rotor through the fixed conduit 33 will sooner or later be returned to the separation chamber 4.

Radial position of throttle hole 37 of annular flange 29 (Fig. 2)
As for the selection of the separation chamber 4, when the change in the amount of oil passing through the throttle hole 37 is passed through the third outflow portion 35, the separation chamber 4 is selected.
It is important because the interfacial layer between the oil and water in the interior results from a radial inward migration. If the throttle hole 37 is disposed relatively close to the rotor with respect to the axis, the interface layer is
When the position of the outflow portion 35 is reached, the oil flow ends relatively quickly, especially if the difference in density between oil and water is relatively large. On the other hand, if the throttle hole 37 is provided relatively far away from the rotor axis, the oil flow through the throttle hole 37 will only be reduced to a greater or lesser extent. If the throttle hole 37 is located far enough away from the rotor axis, even water will be
It is possible to flow out of the rotor through 37 and the flow dividing member 31. This is advantageous if the mixture fed to the separation chamber 4 sometimes contains a significant amount of water.
In such a case, the second outflow part which is the outflow part of the peripheral part
The 12 must be opened relatively frequently, but this opening is limited in frequency so that some water is returned to the container 42. Therefore, the content of water in the mixture in this case is not as high as the content of the mixture having a high water content that is sometimes supplied to the separation chamber 4 as described above, but the water is separated by returning it to the container. Occupying most of the room is prevented. This causes a quantity of water to be discharged from the rotor with the separated oil.

For this reason, the interface layer formed between the oil and the water in the separation chamber 4 during operation of the rotor causes the flow capacity of the throttle holes 37 to supply the amount of water accompanying the new liquid mixture into the separation chamber. If so, it is suitable to be positioned sufficiently away from the rotor axis so as to prevent it from reaching the separating disc 5 radially inward.

In the above description, the liquid exiting the rotor through the fixed conduit 33 is returned to the rotor via the container 42 which feeds the new mixture to the rotor. This is one embodiment of this invention. However, it is possible within the scope of the invention to connect the fixed conduit 33 directly to the inflow conduit 11. Further, some other type of detection device other than the flow rate detection device 38 may be used to initiate the opening of the second outlet 12. For example, a pressure detection device can be used, or a device that detects a change in the dielectric constant of the liquid flowing through the fixed conduit 33 can be used.

Similarly, the separated water flows into the third outflow portion 35 of the separation chamber 4.
Flow rate detector 38 reacts, and if the supplied mixture contains only oil and solids and the interfacial layer between the separated oil and the separated solids reaches outflow 35, The second outlet 12 is opened.

[Brief description of drawings]

FIG. 1 is an axial sectional view of an embodiment of the centrifuge according to the present invention, and FIG. 2 is a partially enlarged sectional view of the centrifuge shown in FIG. 1, 2 ... Rotor, 3 ... Fixing ring 4 ... Separation chamber, 5 ... Separation disk 6 ... Distribution member, 7 ... Bottom plate 8 ... Central space, 9 ... Inflow section 10 ... Inflow pipe, 11 …… Inflow conduit 12 …… Second outflow section (peripheral outflow section), 13 …… Sliding member 14 …… Gasket, 15 …… Closed chamber 16 …… Central inflow section, 17 …… Outflow section 18 …… Center Chamber, 19 ... Inflow member 20 ... Conduit, 21 ... Shut-off valve 22 ... Partition member, 23, 24 ... Annular flange 23a ... First outflow part, 25 ... Central outflow chamber 26 ... Stationary diversion Member, 27 ... Annular passage 28 ... Outflow conduit 29 ... Partition member (annular flange) 29a ... End wall, 30 ... Outflow chamber 31 ... Flow dividing member, 32 ... Annular passage 33 ... Fixed conduit, 34 ... Passage 35 ... Third outflow part, 36 ... Flow path chamber 37 ... Throttling means (throttle hole) 38 ... Flow rate detector 39 ... Control unit, 40, 41 ... Electrical connection line 42 …… Container, 43 ...... Arrow

Claims (7)

[Claims] 1. A rotor (1, 2) rotatable about its central axis, comprising a separation chamber (4) formed in the rotor (1, 2) and the inside of the separation chamber (4). An inflow part (9) of a mixed liquid composed of a light component and a heavy component, which is open to the first side, and a first position which is located at an upper part in the separation chamber (4) at a predetermined distance from the central axis in the radial direction outward. The outflow section (23a), a second outflow section (12) located at the outer peripheral edge of the separation chamber (4), separated from the central axis by a distance larger than the predetermined distance, and the first and second
Of the third outflow (3
5) and a rotor (1, 2), an outflow chamber (30) formed inside the end wall (29a) of the rotor (1, 2), and fixed to the rotor (1, 2) The third outflow portion (3
The passage (34) and the flow passage chamber (3) are provided between the discharge chamber (30) and the discharge chamber (30).
The partition member (22) that forms 6) and the fixed conduit (33) for discharging the liquid to the outside of the rotor (1, 2) communicate with each other through the annular passage (32), and the outflow chamber (30 ) To the inside of the rotor, the flow dividing member (31) extending radially outward to the rotor and opening in the outflow chamber (30), and the sliding member (reciprocable in the central axis direction so as to be able to contact the gasket (14)). 13), a conduit for working liquid formed between the sliding member (13) and the rotor, through the central inflow section (16), the central chamber (18), the inflow member (19), and the closing valve (21). Outflow part (17) connected to (20) and opening to the outside
An opening means (13 to 21) for intermittently opening the second outflow valve, which comprises a closed chamber (15) having an opening, and a third outflow portion (35) and a flow dividing member (31). A throttling means (37) provided between the outlet member (31), the annular passage (32), and the fixed conduit (33) for restricting the flow of the liquid.
A flow rate detecting device (38) provided in the fixed conduit (33) for detecting the flow rate of the liquid in the fixed conduit, the flow rate detecting device (38) and the opening means (13-21). And a control means (39) for controlling the opening and closing of the second outflow part (12) via the opening means (13 to 21) based on the detected flow rate of the flow rate detection device (38). ), The throttling means (37) has a flow capacity smaller than the liquid flow capacity of the flow dividing member (31), the annular passage (32) and the fixed conduit (33). Centrifuge. 2. A throttle means (37) communicates with an outflow chamber (30) into which a flow dividing member (31) extends, and a third outflow portion (35), and inside the rotor during operation of the rotor. The partition member (2) formed in the rotor is formed between the flow path chamber (36) extending inward in the rotor so that a free liquid surface is formed.
9. The centrifuge according to claim 1, characterized in that the centrifuge is arranged inside. 3. The fixed conduit (33) forms an annular flow path to a separation chamber (4) for the liquid discharged from the rotor to the outside through the third outflow portion (35). Item 1 or 2
The centrifuge according to the item. 4. A container (42) for supplying the mixed liquid to the separation chamber (4) of the rotor, wherein a fixed conduit (33) opens into the container (42). Centrifuge according to claim 3. 5. A set of conical separating discs (5) is arranged in the center of the separating chamber (4) and a throttling means (37) is arranged sufficiently far from the axis of the rotor that the light liquid component and The interface layer formed between the heavy liquid components radially inwardly separates the separation disk (5) while the flow capacity of the throttle means (37) exceeds the supply amount of the heavy liquid components to the separation chamber (4). 5.) Centrifuge according to any one of claims 1 to 4, characterized in that it is prevented from reaching up to. 6. A flow detection device (38) according to any one of claims 1 to 5, characterized in that it is arranged to detect a change in flow in the fixed conduit (33). The described centrifuge. 7. The first outlet (23a) constitutes the outlet of the separated light liquid components of the mixture from the centrifuge,
A second outlet (12) of the rotor constitutes the only outlet from the centrifuge of the separated solids of the mixture and the separated heavy liquid constituents. 7. The centrifuge according to any one of items 6 to 6.